LEMMA 3 
(compare with [1]}, Lemma 2)
Let \( F,C,X\)  and \( N(F)\)  be as in Lemma REF . Then there exists \( r \in N(F)\)  such that for any \( f\in N(F),\)  \(x \in C\)  and \( y \in F\)
\(\Vert  y - f(r(x))\Vert  = \Vert y - r(x)\Vert .\) 

